If it's just a question of partitioning and formatting a second drive, then the built-in tools will do the job just fine. If you want to divide an existing disk into two partitions (which may not be the most sensible thing to do as far as performance is concerned) you can again use the built-in tools. Have a look at this article
which tells you how to shrink your existing partition and create a new one in the space freed up. But I can't see that you would gain any advantage by partitioning a single disk.
Two words of warning.
1. I have seen reports that Disk Management won't shrink the C: drive in some circumstance, which would mean that you might need to use one of the third-party tools. In any case there is a limit to how much you can shrink it.
2. If you do want to shrink your existing C: drive then make sure that you have a separate backup of any important data and that you have the means to reinstall Windows if necessary (i.e. a Windows install DVD). These things don't often go wrong, but if something did you could be left with an unbootable system and lost data.